package com.sir.tao.carhire.shiro;

import lombok.SneakyThrows;
import lombok.extern.slf4j.Slf4j;
import org.apache.shiro.authc.AuthenticationException;
import org.apache.shiro.web.filter.authc.BasicHttpAuthenticationFilter;
import org.springframework.http.HttpStatus;
import org.springframework.stereotype.Component;
import org.springframework.web.bind.annotation.RequestMethod;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * @author dyy
 * @data 2021/12/6 16:31
 * @description:
 */
@Component
@Slf4j
public class JwtFilter extends BasicHttpAuthenticationFilter {
    /**
     * 跨域支持
     * @param request 请求
     * @param response 响应
     * @return 返回
     */
    @Override
    protected boolean preHandle(ServletRequest request, ServletResponse response) throws Exception {
        log.info("执行跨域");
        HttpServletRequest httpServletRequest = (HttpServletRequest) request;
        HttpServletResponse httpServletResponse = (HttpServletResponse) response;
        httpServletResponse.setHeader("Access-control-Allow-Origin", httpServletRequest.getHeader("Origin"));
        httpServletResponse.setHeader("Access-Control-Allow-Methods", "GET,POST,OPTIONS,PUT,DELETE");
        httpServletResponse.setHeader("Access-Control-Allow-Headers", httpServletRequest.getHeader("Access-Control-Request-Headers"));
        // 跨域时会首先发送一个option请求，这里我们给option请求直接返回正常状态
        if (httpServletRequest.getMethod().equals(RequestMethod.OPTIONS.name())) {
            httpServletResponse.setStatus(HttpStatus.OK.value());
            return false;
        }
        return super.preHandle(request, response);
    }

    @SneakyThrows
    @Override
    protected boolean isAccessAllowed(ServletRequest request, ServletResponse response, Object mappedValue) {
        HttpServletRequest httpRequest = (HttpServletRequest) request;
        String uri = httpRequest.getRequestURI();
        if (uri.contains("car-hire/error")){
            return true;
        }
        if (isLoginAttempt(request, response)) {
            try {
                //如果有token
                executeLogin(request, response);
            } catch (Exception e) {
                request.getRequestDispatcher("/authenticationException").forward(request, response);
                throw new AuthenticationException("Token失效，请重新登录", e);
            }
        }else {
            request.getRequestDispatcher("/authenticationException").forward(request, response);
            throw new AuthenticationException("Token失效，请重新登录");
        }
        return true;
    }

    @Override
    protected boolean isLoginAttempt(ServletRequest request, ServletResponse response) {
        HttpServletRequest hsr = (HttpServletRequest) request;
        String authorization = hsr.getHeader("Authorization");
        return authorization!=null;
    }

    @Override
    protected boolean executeLogin(ServletRequest request, ServletResponse response) {
        HttpServletRequest httpServletRequest = (HttpServletRequest) request;
        //从请求头中获取token
        String authorization = httpServletRequest.getHeader("Authorization");
        //放入对象中, redis或者数据库查询  等同于之前的UsernamePasswordToken
        MyJsonWebToken token = new MyJsonWebToken(authorization);
        // 提交给realm进行登入，如果错误他会抛出异常并被捕获
        //这个等同于直接的 subject.login(token)
        getSubject(request, response).login(token);
        // 如果没有抛出异常则代表登入成功，返回true
        return true;
    }
}
